When some items in a menu are selected more frequently than others, as
is often the case, designers or individual users may be able to speed performance and improve satisfaction by placing several high-frequency items at the top of the menu. Design guid
elines for split menus were developed and applied. Split menus were implemented and tested in two field studies and a controlled experiment. In the field study conditions performance times were reduced from 17 or 58% depending on the site and menus. In
the controlled experiment split menus were significantly faster than alphabetic menus and yielded significantly higher subjective preferences. A possible resolution to the continuing debate among cognitive theorists about predicting menu selection times
is offered. We conjecture and offer evidence that the logarithmic model applies to familiar (high-frequency) items and the linear model applies to unfamiliar (low-frequency) items.

The HCIL has a long, rich history of transforming the experience people have with new technologies. From understanding user needs, to developing and evaluating these technologies, the lab's faculty, staff, and students have been leading the way in HCI research and teaching.